Biological Response Indicators Resource Project Summary/Abstract The Biological Response Indicators Resource in the Minnesota CHEAR Exposure Assessment Hub will measure a variety of validated biological response indicators that will inform the consequences of environmental exposures in children. The investigators in the Resource have vast experience in the analytical chemical and biological methods required for these analyses as well as a broad understanding of the mechanistic consequences and health implications of these measurements. The Biological Response Indicators will provide timely and reliable measures in several distinct responses: 1) Measures of DNA damage from environmental chemicals; 2) Measures of oxidative and lipid peroxidative stress and inflammation and 3) Measures of epigenetic changes. While the DNA adducts are lower throughput assays, many of the proteins/lipids and metabolites are higher throughput assays. Assays for DNA adducts and the small molecule markers of inflammation and oxidative stress involve sensitive LC-MS/MS methods that use stable isotope internal standards. The larger molecules are quantified with validated ELISA assays. Many of these assays have been applied by the investigators in this Resource in multiple clinical and epidemiological studies in which hundreds or thousands of samples have been processed.